Progress in in-situ CO2-sorption for enhanced hydrogen production

Deployment of fossil fuels to quench the energy demand of the world's rising population results in elevated levels of greenhouse gas (GHG) emissions, especially CO2, which in turn is responsible for undesirable climate change. This necessitates a shift toward cleaner energy resources such as hydrogen. Enhanced hydrogen production via steam reforming of diverse fuels (methane, biomass, organic wastes, etc.) with in-situ CO2-sorption seems to be a promising alternative. Leading-edge, innovative and eco-friendly pathways coupled with high process efficiencies are needed for the development and growth of this technology. This review article evaluates the fundamental concepts such as criteria for CO2 uptake, mechanisms, thermodynamics and kinetics of the water gas shift reaction along with different modeling methods for sorption enhanced processes. Moreover, research works carried out worldwide at lab-scale coupled with process development and demonstration units are discussed as a means to encourage this pathway for H-2 generation. Furthermore, light is shed on techno-economics as an approach to improve the viability and sustainability of the proposed technology. This paper analyzes different dimensions of the CO2-sorption enhanced process to promote it as a potentially carbon-neutral and ecofriendly pathway for hydrogen production